If you spend time online as part of your daily routine, you know that staying productive while browsing the Web is a challenge. Fortunately some great websites and browser extensions are available to help transform your browser into one of the most powerful productivity tools in your arsenal. Elsewhere we've discussed how to avoid tech distractions in your daily life; in this article we'll discuss three of the most popular productivity and time management systems, along with some great browser modifications to help you stick to them.

Try Pomodoro

Francesco Cirillo's Pomodoro technique is a time management system designed to limit the amount of time you waste during your workday. The system divides the workday into 25-minute Pomodoro periods; Cirillo named them after the timer shaped like a tomato (pomodoro in Italian) that he used to keep himself on track.

Cirillo came up with the system when he realized that he was incapable of focusing on a task nonstop for an extended period of time, and that without some sort of practical regimentation his attention often got diverted into unproductive activities for long stretches of the workday. To rein in this tendency, Cirillo placed a kitchen timer on his desk and set it for a 25-minute block of time. He would then work as hard as he could on a specified project until the timer rang--at which point he would take a short break, getting up from his desk and allowing his mind to wander freely. By structuring his workday into these prearranged periods of focused work and free time, Cirillo found that he could deal with the distractions in his life without sacrificing his productivity.

Cirillo recommends that you use a physical timer so you can't ignore it, but some people find that an on-screen reminder is more helpful. Quite a few Pomodoro timers are available as stand-alone apps for your PC, smartphone, or tablet, but our favorite is a Chrome extension called Chromodoro. When you install Chromodoro, a small tomato icon appears in your browser address bar. It stays discreetly out of the way until you click on it; but once you do, the extension counts down a standard 25-minute Pomodoro cycle and notifies you when the work period is over and it's time to take a break.

The Chromodoro browser extension is unobtrusive and simple to use.

The Chromodoro extension is free and customizable. If you're building up to a full 25-minute Pomodoro cycle or you want to adjust with the work/rest periods into a pattern that suits you better, Chromodoro lets you customize the length of both your Pomodoro period and your break.

Getting Things Done

Getting Things Done (GTD), a popular personal productivity system created by David Allen, is easily the most complex productivity system of the three we recommend. Still, the core premise of Allen's system is straightforward: We rely far too much on our imperfect memories to help us organize tasks and get work done. Trying to keep track of multiple projects leads to human error as we forget important tasks and waste time worrying over which project we should be working on at any given moment.

The solution: As soon as you remember a task, write it down so that your fallible, distractable brain isn't the only place where you're storing a record of it. This is the core principle of Getting Things Done. If you use it while working online, identifying your next task is a simple matter of consulting your to-do list.

Many developers have produced great standalone GTD apps, but most are platform-specific and tie you to a specific device such as a smartphone, a tablet, or a pad of paper. For GTD (or for any to-do-list system, really), we recommend using an elegant service like Remember the Milk, which is free and offers extensions for all major browsers.

Remember the Milk is free, easy to use, and perfect for keeping your task list updated on the go.

Adding new tasks to Remember the Milk as part of the Getting Things Done approach involves opening the RtM website in your browser of choice, typing your task in, and then returning to your current task. We recommend Remember the Milk because it lets you organize tasks into different groups, which is a major element of the GTD process. Since Remember the Milk also has a great mobile interface (plus free apps for iOS, BlackBerry, and Android), you can record a task while you're on the go and count on its being automatically synced with your GTD task list the next time you sit down to get some work done.

Don't Break the Chain

Don't Break The Chain was popularized by comedian Jerry Seinfeld, but it has evolved into a productivity system with some significant cognitive science behind it. When Seinfeld first began working as a stand-up comedian, he wanted to write new material every day, so he came up a technique to keep himself on track. Seinfeld bought a wall calender and hung it up in a spot where he would have to look at it daily; every day he wrote new material, he would mark a big X on the calendar for that day. Over time, the unbroken chain of successful days grew bigger and bigger, and it became a great motivational tool to keep the string going, even on days when he didn't feel like doing any writing.

A very useful Web version of Seinfeld's calendar can help you be more productive during your work week. The free DontBreaktheChain.com service lets you tick off your daily goals online, as you complete them, and you can access your Don't Break the Chain info from any Web browser. Unlike a traditional wall calendar, Don't Break the Chain lets you customize the number of months you can see simultaneously. So whether you're approaching four months or four years of an unbroken chain, your track record is visible at a glance. The service even lets you maintain multiple chains at once, by assigning color codes to different projects--a great way for freelancers or small business owners to simultaneously manage multiple productivity goals.

Don'tBreaktheChain.com lets you keep a visual record of how productive you've been, and you can color-code your records based on your goals.

To replicate the effect of setting up a calendar in a location where you'll see it each day, consider making DontBreaktheChain.com your browser's homepage. That way you'll see it every time you start up your browser or open a new tab.

The tools we've been discussing are mutually compatible. Though I wouldn't recommend trying to start all three systems at once, they complement each other extremely well if you decide you need to phase in another productivity system to help you accomplish your goals. Pomodoro is a great tool for encouraging day-to-day productivity, GTD helps with project management and staying organized, and Don't Break the Chain offers visual motivation to keep working when you might be tempted to quit. Put the browser hacks for each system together, and soon your Web surfing habits will sculpt you into a lean, mean productivity machine.

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